Known boxing machines comprise an initial grouping unit where a number of lines of successive adjacent individual packages are formed; and a final grouping unit where a number of lines of packages are superimposed to form groups of packages. Downstream from the final grouping unit, a packing unit packs each group of packages into a respective cardboard box.
The packing unit comprises a blank store containing a stack of flat blanks; a packing belt conveyor with a succession of pockets; and a feed device which withdraws the first blank in the stack by suction and inserts it into a pocket on the packing conveyor; as it is inserted into the pocket on the packing conveyor, the blank is folded onto a ‘U’. Next, a group of packages is inserted longitudinally into a packing conveyor pocket containing a U-folded blank, and the blank is gummed (i.e. glued) and folded further about the group of packages to form a cardboard box.
A unit of the above type described in document JP2004299708 comprises a packing conveyor with two pairs of side by side conveyor belts. So the blank is conveyed along the packing path inside pockets defined by the gaps between spacers on the conveyor belts. More specifically, the pockets are adjustable to adapt the seats to the content being conveyed.
Known packing units of the above type work well, but have the major drawback of not being very flexible. The flexibility of the conveying part does not match up with that of the packing unit as a whole, especially as regards feeding the blanks and unloading the finished containers. That is, chancing the blank format (i.e. size) involves changing several component parts on the packing unit. This is a particularly painstaking, time-consuming job requiring skilled labour, in that, in addition to removing parts and assembling new ones, the packing unit as a whole must be set up to make sure the new parts interact properly with the rest of the unit. This lack of flexibility is an increasingly important issue in view of the general market tendency towards small production lots with frequent changeovers.